SOLUTION: I am not sure if I chose the right topic to type this under: I have to use the substitution method to solve systems of equations. the problem I have is: 2x + 2y = 41 x + 2y = 0

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Question 490758: I am not sure if I chose the right topic to type this under: I have to use the substitution method to solve systems of equations. the problem I have is:
2x + 2y = 41
x + 2y = 0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Start off by solving for x in the second equation to go from x%2B2y=0 to x=-2y


Now go back to the first equation and replace each copy of x with -2y (this is legal since x = -2y)


So the first equation goes from 2x%2B2y=41 and becomes 2%28-2y%29%2B2y=41


This is why this method is known as the substitution method. In that last step, I substituted x for -2y. Doing this got rid of one variable so you can solve for the other.


So at this point, you have a linear equation with one variable (y). Solve this equation to find the value of y. Once you have y, use that to find x. You do this by plugging it into x=-2y and evaluating.